'Super' El Nino talk is too early and it doesn't exist anyway, experts say

The Bureau of Meteorology still says an El Nino is building but officially it is still a 50 per cent chance, or twice the normal likelihood.

Reports the three years of flooding La Nina will be replaced by the drying El Nino have spooked many people.

BOM meteorologists say they do not use the term "super El Nino" which they say has no scientific basis.

In its latest climate forecast the nation's public weather forecaster again warns accuracy of its own and other international global computer models have a much lower accuracy at this time of year and "caution is needed".

BOM's ENSO Outlook remains at El Nino watch.

"A significant amount of warmer than average water exists in the sub-surface of the western and central tropical Pacific Ocean, and warm sea surface temperatures anomalies continue to strengthen in the eastern tropical Pacific," BOM's latest update states.

"The Southern Oscillation Index has decreased to negative values over the past fortnight. Warming ocean temperatures in the eastern and central tropical Pacific and decreasing SOI values can be a precursor of El Nino development."

BOM forecasters say El Nino watch is not a guarantee El Nino will occur, rather an indication some of the typical precursors are currently occurring.

All climate models surveyed by the bureau suggest El Nino thresholds are "likely to be approached or exceeded during the southern hemisphere winter".

From July, all but one of the international models indicate El Nino thresholds will be met or exceeded, with all models by August.

The bureau is forecasting below median rain is "likely to very likely" for May to July for most of Australia while maximum temperatures are likely to be warmer than median.

Meanwhile, Tropical Cyclone Ilsa is impacting inland areas of the eastern Pilbara, with its destructive winds moving inland between Marble Bar and Telfer.

During today, TC Ilsa is forecast to maintain tropical cyclone intensity as it tracks past Telfer and further inland across the northern parts of the Interior.

TC Ilsa is then expected to weaken below tropical cyclone strength overnight tonight as it moves into southern parts of the Northern Territory.